Safety-crank for explosion-engines.



' W. R'. CLARK. SAFETY GRANK FOR EXPLOSION ENGINES. APPLICATION FILEDDEO. 10, 1910.

1 ,020,799. v Patented-Mar. 19, 1 912.

l ll g.

ATTORNEY.

eol

UNTED STATES ATENT OFFICE.

`WILLIA1VI R. CLARK, OIF MUNCIE, INDIANA.

SAFETY-CRANK FOR EX?LOSIONENGINES.

To a?! whom it may concern Be it knoun that I, VTLLIAM R. CLARK, a citizen of the ln'ited States, residing at Muncie,` in the county of Delaware and State of Indiana.l have invented a new and useful Safety-Crank for Explosion-Engines, of which the folloving is a specification, reference being had to the accompanying drawings and to the letters and figures of reference marked thereon.

This invention relates to apparatus for starting or cranking l explosion engines, especially the compression type of automobile engines, and the invention has reference more particularlyto means, associated with hand cranking apparatus, designed to disconnect the hand crank from the crank shaft of the engine after starting, especially in case the engine starts in reverse to normalV direction, or kicks back, when an effort is made to start the engine.

The object of the invention is to provide improved cranking apparatus for explosion engines that Will enable the startingto be accomplished by handvvithout risk of injury to the operator, in case. an engine starts backward While an effort is being made to start it for normal operation; a further object being to provide a safety hand crank of simple construction that` will be adapted to be used Without liability to injure the operator when the enginestarts promptly in the proper direction 'Wit-li the hand crank connected with and urging the crank shaft of the engine forward The invention consists in a hand crank and devices for coupling it temporarily with the crank shaft of an engine and provided with an improved automatic coupling` breaker adapted to uncouple the hand crank from the crank shaft when the latter starts backward; the apparatus comprising also an improved automatic main throw-off device for enabling the engine to proceed when started in normal direction Without carrying the hand crank With it, and an improved auxiliarv throw-oil device adapted to perform the function of the main throwofi" device in case the main device sticks fast or fails to properly operate.

The invention consists also specifically in the novel parts, and combinations and arrangements of parts, as hereinafter particularly described and claimed.

Specification of Letters Patent.

Application filed December 10, 1910.

Patented Mar. 19, 191:2.

Serial No. 596,571.

Referring to the drawings, Figure l is a fragmentary .end elevation of an explosion engine with which theinvention 1s connected; Fig. 2, a fragmentary sectional elevation of the engine and the invention connected therewith approximately on the line A A in Fig. 1; Fig. 3,- a sectional view of the invention as preferably constructed also on the line A A on an enlarged scale, with the hand crank uncoupled from the crank shaft; Fig. 4, a fragmentary sectional elevation showingthe stub shaft of the hand crank coupled to the crank shaft of the engine; Fig. 5, a fragmentary sectional elevation approximately on the line B B in Fig. 3; and Fig. (S, an end vieiv of parts of the invention which are permanently connected to the crank shaft of the engine.

Similar reference characters indicate corresponding elements or features of construction throughout the drawings.

The engine shown for the purpose of explaining the construction and function of the invention comprises a suitable frame l, a crank box 2, one or more cylinders 3 in each of which is a piston 4, a shaft 5 being mounted in the crank box and having cranks 6 thereon, e'ach crank being connected by a pitman 7 with a piston, a radiator 8 usually being mounted on the frame ahead of the engine.

The crank shaft 5 is provided with suitable devices ivith which other devices may be connected for coupling the hand crank to the crank shaft for starting operations. and in order to apply the invention to existing engines a coupling member 9 is provided which has a socket 10 therein to receive the forward end portionl of the crank shaft, the member being secured permanently to the crank shaft preferably by a set-screw 11. The opposite or router end portion` of the member 9 has a smooth bore` 12 therein for guidingone end of al stub shaft, and within the bore a suitable number of clutch teeth 13 of ratchet form are provided, the teeth having bluntor iattened extremities and squared faces 13 facing rearward and inclined faces 13 facing forward with re-A spect to normal direction of movement. The teeth 13 preferably are formed on a separate'core 14 pressed tightly into the bore 12 and further` secured by a in 15 or otherwise to the member 9, in or er to facilitate accurate construction of the teeth. The shaft '5 starts to turn backward it starts the bored end of the member 9 has an external groove 16 therein, and a coupling breaker lis mounted on said bored end, being preferably constructed as an annular collar 17 rota tive on said end portion and provided with a guide-pin'18 screwed through the collar and into the groove, the collar having ratchet teeth 19 on its periphery arranged with the squared sides thereof facing rearward.,A A bracket 20-is suitably secured vto theframe 1 or otherwise, so as to be fixed adjacent to the collar,land it has a dog 21 clutch teeth 23 on its outer face, the teeth,

lbeing of the ratchet type flattened on their mounted movably therein and pressed by a spring 22 intocontact with the ratchet teeth 19, the dog being adapted to serve. as a ratchetpawl and prevent backward m'ovement of the collar while permitting the collar to move forward or in the normal direc-V tion of rotation of the crank shaft. The collarA is provided with a suitable number of extremities and havingV squared sides 23' facing rearward and inclined sides 23 facing forward. This construction of the teeth 23 enables the collar to be turned forward either with or independently of the mem- I ber 9.

'the teeth 25 also having flattened extremities and are of the ratchet type with squared .sides facing forward and inclined sides facing rearward. The stub shaft is guided rotatively in the bore 12 and may be moved longitudinally therein so that when it is .turned to the right' and pushed inward the crank shaft is turned to the right or normal direction of motion for starting the engine, and it will be clear' that when the engine starts normally and turns the -crank shaft'y faster than the stubrk shaft, the latter is forced outward by the teeth 13 so that the teeth become uncoupled from the teeth 25.

The stub shaft has a cylindrical flange-like.

projection-26 thereon at a suitable distance from the inner end thereof, and the vside of the rejection toward the collar 17 has clutc teeth 27 thereon with flattened eX- tremities, the teeth having squared sides facing forward and inclined sides facing rearward and adapted to engage the teeth 23,y for turning the collar in normal direction, and 'it will ,be apparent 'that if the crank shaftfturns forward and the stub shaft fails to become uncoupled therefrom en- 'tirelyg' the stub shaft on being slightly turned backward is caused by the teeth 23 and 27 to be moved outward so that the teeth 25 clear the teeth 13, it being seen that the teeth 23. and-27 are longer than the teeth 13 .stub `shaft backward and causes the teeth 23 to force the teeth outward quickly so as to force the teeth 25 entirely away from the teeth 13, the collar 17 having the teeth 23 thereon being prevented from turning backward by the dog 21.

In order to guard against possible acei- `dental injury to the operator when the envhaving squaredsides facing rearward and inclined sides facing forward, so that these `teeth are like the teeth 23 on the collar 17.

A sleeve 29 is mounted rotatively on the stub shaft 24 and is movable longitudinally thereon, and itsinner end is provided with a flange 30 that has ratchet type teeth 31 on the side thereof that faces toward the projection 2G, the-teeth 31 having squared sides facing forward and inclined sides facing rearward, these teeth being like the teeth 27, so that when the sleeve is pushed inwardlythe teeth 31 are brought into engagement with the teeth 28 for locking the sleeve to the stub shaft to .turn the latter i to the right for cranking the engine, and it is apparent that in case the stub shaft is carried to the right bythe crank shaft while the sleeve is stopped the teeth 28 forces the teeth 31 outward so as to disconnect the sleeve from the stub shaft. 32 is secured to the sleeve 29 preferably by a set-screw 3 3. A suitable arm 3l is` supported fixedly in any desired manner, pref- ,er'ably o-n t-he'bracket 20, and is provided A hand crank with a bearing end 35 vadapted to support the sleeve and thereby the outer end of the stub shaft and to be engaged by the flange 30, for limiting the outward 4movement of the sleeveon the stub shaft, the bearing end preferably being constructed as a journalboX and provided with a cap 36.

It will be understood, that the collar 17 comprising the principal part of the coupling` breaker. maybe prevented from turning backward by other means than the ratchet teeth 19 and dog 21.

In practical use the hand crank 32 is pushed toward the engine and turned to the right or in the direction that the engine normall' runs until explosion occurs when, the. cran. shaft rotating faster than the stub shaft becomes automatically uncoupled from the hand crankthrough the intermediate .means vliereinbefore described, the particular functions of which having been' particularly pointed out;l and, in case the enginev starts backward, or kicks backward, the

fil@ and 25. Alge, `itlatral that if the @sur Stub shaft is automatically @coupled from the crank shaft as above explained, so that the hand crank 32 can not be forced backward to any appreciable extent.

Having thus described the invention, what is claimed as new, is-

crank forl explosion en' 1. In a safety gines, the comblnation with a crankshaft provided with clutch teeth, of a stub shaft having clutch teeth thereon for detachably engaging the clutch teeth of the crank shaft,

the stub shaft being rotatably supported and having a cylindrical flange-likeprojection thereon, va collar supported to rotate about the stub shaft, means for enabling the projection to rotate the collar in one direction,

end portion thereof, said opposite end perf' tion having a smooth bore and provlded therein with clutch teeth, a collar rotatably mounted on said opposite end portion and covering said groove, said collar having ratchet teeth on its periphery, a guide pin screwedinto said collar and extending into said groove, clutch teeth on the outer face of said collar,`a support fixed adjacent to said collar, a dog mounted movably in said support, a spring seated in said support and pressing said dog int-o engagement with saidratchet teeth, a stub shaft extending 4into said bore and having a fiange-like projection thereon, clutch teeth on said projection to engage the clutch teeth on the face of said collar, clutch teeth on said stub shaft' for engaging the clutch teeth of said coupling member, and a hand crank for rotating said stub shaft.

3. In a safety crank for explosion engines, the combination with a fixedly supported bracket, and a coupling member rotative adjacent the bracket and rovided with clutch teeth and also a smoot bore,.the coupling member being adapted for connection with a crank shaft, of a collar guided rotatabl -i on said member and having ratchet tee thereon, a Idog inovably supported by said bracket adjacent said collar, a spring vs upported by said bracket and pressing said dog into engagement with said ratchet teeth, ,y v

clutch teeth on one side of said collar, a stub shaft having a cylindmcal flange-like rojection thereon, said shaft extending' into said bore, clutch teeth on the'inner end of 7 said` shaft to engage the teeth with which said coupling member is provided, clutch teeth`on the inner side of said projection opposed to the teeth on said collar, clutch teeth on the outer side of, said projection, a sleeve rotative on said shaft and having a flange on one end thereof, clutch teeth` on said flange opposed to the teeth on thev outer side of said projection, and a hand crank secured to the opposite end portion of said sleeve.

'4. In a safety crank for explosion engines, the combination with a rotatable crank shaft, and a fixed support, of a stub shaft provided with clutch devices and having a-V cylindrical flange-lke projectionl thereon provided with two series of oppositely facing ratchet type clutchV teeth, said teeth having flatt ned extremities, a coupling member connected to the crank shaft and having a bore therein receiving'on'e end of'said stub shaft, said member beinghprovided with clutch devices to be engaged by the clutch devices on the stub shaft, a collar rotatable on said coupling member, a device coper` ating with said support and said collar for detachably connecting said collar to said support, ratchet type clutch teeth on said collar having flattened extremities and op-` posed to one of the series of clutch teeth on.

said projection, a sleeve rotatable on said shaft and having a flange on one end thereof, ratchet type clutch teeth on said flange opposed to the other of the two series of teeth on said projection, and a hand vcrank secured to said sleeve.

In testimony whereof, I affix my signature in presence of two witnesses.'

WILLIAM R. CLARK.

Witnesses: i

P. A. HAVELICK, E. T. SiLvIUs.

Copies ot this patent maybe obtained for ve cents each, by addressing the Commissioner of Patents. Washington, D. C. 

